Pyrazolyl-azo-indole dyestuffs

ABSTRACT

PYRAZOLPY-AZO-INDOLE COMPOUNDS PRODUCE BRIGHT YELLOW SHADES ON HYDROPHOBIC FIBERS AND EXHIBIT EXCELLENT FASTNESS TO LIGHT. THE PYRAZOLYL DIAZO COMPONENT IS SUBSTITUTED WITH A CYANO, CARBAMOYL, NITRO OR ALKOXYCARBONYL GROUP ON THE RING CARBON ADJACENT OT THE CARBON ATOM BONDED TO THE AZO GROUP.

3,634,391 PYRAZOLYL-AZO-IIN DOLE DYETIUFFS John G. Fisher and Clarence A. Coates, .lra, Kingsport,

Tenn, assignors to Eastman Kodak Company, Rochester, N.Y.

No Drawing. Continuation-impart oi application Ser. No. 610,798, Jan. 23, 1967. This application July 25, 1969, Ser. No. 845,085

Int. Cl. C69]: 29/36 US. Cl. 260l62 7 Claims ABSTRACT OF THE DISCLOSURE Pyrazolyhazo-indole compounds produce bright yellow shades on hydrophobic fibers and exhibit excellent fastness to light. The pyrazolyl diazo component is substituted with a cyano, carbamoyl, nitro or alkoxycarbonyl group on the ring carbon adjacent to the carbon atom bonded to the azo group.

This application is a continuation-in-part of our coending application Ser. No. 610,798, filed Jan. 23, 1967 for Pyrazolylazo Cations, now abandoned.

This invention relates to certain novel azo compounds and, more particularly, to certain pyrazolylazoindole compounds which are useful for dyeing hydrophobic textile materials.

The novel pyrazolyl compounds of the invention have the general formula wherein The compounds of the invention impart bright yellow shades of excellent fastness properties to hydrophobic textile materials such as cellulose acetate, nylon and, especially, polyester fibers. For example, the novel azo compounds possess improved fastness to light when compared to the azo compounds disclosed in US. Pat. 3,435,022.

Methyl, ethyl, propyl, isopropyl, butyl and isobutyl are typical of the alkyl groups which R R R R and R can represent. Examples of the alkoxy groups represented by R and R include methoxycarbonyl, ethoxycarbonyl, isopropoxycarbonyl, and butoxycarbonyl. Z-hydroxyethyl and 2,3-dihydroxypropyl are examples of the hydroxyalkyl groups which R can represent. Acetyl, propionyl, butyryl, methylsulfonyl, ethylsulfonyl, propylsulfonyl and isobutylsulfonyl are representative of the alkanoyl and alkylsulfonyl groups represented by R The aryl groups represented by R and R and the aryl moiety of the arylcarbonyl and arylsulfonyl groups represented by R nited States Patent 0 'ice can be unsubstittued phenyl or phenyl substituted with lower alkyl, lower alkoxy, halogen, or nitro. Phenyl, p tolyl, p-ethoxyphenyl, o,p-dirnethylphenyl, m-chlorophenyl, m-nitrophenyl, p-tolylsulfonyl, p-anisylsulfonyl, benzoyl, p-toloyl, p-bromophenylsulfonyl, m-bromobenzyl, etc. are typical of such aryl, arylcarbonyl, and arylsulfonyl groups. 2-cyanoethyl, 3-acetamidopropyl, 3- butyramidopropyl, Z-carbamoylethyl, 3-benzamid0propyl, 3-butylsulfonamidopropyl, 3-phthalimidopropyl, 3-suc cinirnidopropyl, S-glutarimidopropyl, 3 p tolylsulfonamidopropyl, 2-carboxyethyl, benzyl, Z-phenylethyl, ethyl- NHCONH-propyl and phenyl-NHCONH-propyl are examples of the substituted alkyl groups represented by R Additional examples of the aryl groups and the alkanoyl, arylcarbonyl, alkylsulfonyl, and arylsulfonyl moieties of the acylamido groups which can be present on the substituted alkyl groups represented by R are set forth above. Methoxy, ethoxy, propoxy, and isobutoxy are typical alkoxy groups which R can represent. Bromine and chlorine are illustrative of the halogen atoms represented by R.

A preferred group of the azo compounds of the invention have the formula wherein R is cyano or lower alkoxycarbonyl; R is lower alkyl, phenyl, or phenylsulfonyl; and R is lower alkyl, cyanoethyl, lower alkanoylamidopropyl,

phenyl-NI-lCONH-propyl or succinimidopropyl.

The novel azo compounds are prepared by diazotizing an aminopyrazole having the formula:

( R -H R2 and coupling the resulting diazonium salt with an indole coupler having the formula:

(III) i t R the aminocarbamoylpyrazoles are prepared by the hydrolysis of the corresponding aminocyanopyrazole; the aminoalkoxycarbonylpyrazoles can be prepared by the reaction of an ethoxymethylene cyanoalkylacetate (Ben, 38, 51) with as described in Helv. Chim. Acta. 39, 4597; rearrangement of the appropriate isoxazole in the presence of a hydrazine as described in Gazz. Chim. Ital., 72, 537 (Chem. Abs., 38, 4597) gives the aminonitropyrazoles; and the aminodicyanopyrazoles are obtained by reacting tetracyanoethylene with the appropriate hydrazine as described in J. Org. Chem., 29, 1915.

Exemplary aminopyrazoles corresponding to Formula 11, prepared as set forth above, which are diazotized and coupled with the indole coupling components include 3-amino-4-cyanopyrazole, 3-arnino-4-nitropyrazole, 3-aminopyrazole-4-carboxamide, 3-amino-4-cyano-2-phenylpyrazole, 3-amino-4,S-dicyano-2-phenylsulfonylpyrazole, 3-amino-2-phenylpyrazole-4-carboxamide, 3-amino-4-nitro-2-phenylpyrazole, 3-amino-5-methyl-4-nitro-2-phenylpyrazole, 3-aminc-4-cyano-Z-methylpyrazole, 3-amino-4-cyano-2-p-toluoylpyrazole, 3-amino-4-cyano-2,fi-hydroxyethylpyrazole, 3-amino-4-cyano-2-p-nitrophenylpyrazole, 3-amino-2,p-chlorophenylpyrazole-4-carboxamide, 3-amino-4-cyano-2,p-tolylpyrazole, 3-amino-4,5-dicyano-2-methylsulfonylpyrazole, 3-aminopyrazole-4-carboxylic acid methyl ester, 3-amino-2-phenylpyrazole-4-carboxylic acid methyl ester, 3-amino-2-phenylsulfonylpyrazole-4-carboxylic acid methyl ester, 3-amino-2-methylpyrazole-4-carboxylic acid methyl ester, 3-aminopyrazole-4-carboxylic acid ethyl ester, 3-aminopyrazole-4-carboxylic acid isopropyl ester, 3-amino-2-phenyl-4-carboxylic acid isopropyl ester, 3-amino-2-phenylsulfonylpyrazole-4-carboxylic acid isopropyl ester and the like.

Examples of the indole couplers include l-methyl-Z-phenylindole,

1,2-dimethylindole,

1,2-dimethyl-S-chloroindole,

2-phenylindo1e,

1- 3-cyanopropyl -2-phenylindole,

1-ethyl-2-phenyl-5-ethylindole,

1- (Z-cyanoethyl) -2-phenyl-6-bromoindole,

2-phenyl-1-butylindole,

l-methyl-2-phenyl-5 ,6-dichlroindole,

1-methyl-2-phenyl-5-ethoxyindole,

1,2-dimethyl-7-chloroindole,

1-methyl-Z-phenyl-S-ethoxycarbonylindole,

1- 2-cyanoethyl -2-phenyl-6-methoxyindole,

1- 3-succinimidopropyl) -2-ethyl-6-methoxycarbonylindole,

1-methyl-2-phenyl-5-bromoindole,

1,2-dimethyl-S-nitroindole,

1-(3- benzamidopropyl)-2-phenylindole,

1- (3-propionamidopropyl) -2-p-tolylindole, etc.

The preparation of the aminopyrazoles, the novel azo compounds and the use of the novel compounds is further illustrated in the following examples.

EXAMPLE A Preparation of ethoxymethylene methylcyanoacetate A mixture of methylcyanoacetate (99 g.), triethylorthoformate (148 g.) and acetic anhydride (220 g.) is heated at total reflux in a distillation flask with a twelve inch Vigreux column for three hours. Take off of refluxing vapors is begun and continued at atmospheric pressure until the head temperature reaches 120 C. After cooling, the system is put under vacuum and the product collected at 99 C./0.3 mm. after discarding a small forerun. A yield of 67.5% is obtained; the refractive index of the liquid is 1.4842 at C.

4 EXAMPLE B Preparation of 3-aminopyrazole-4-carboxylic acid methyl ester Hydrazine hydrate (6.5 g.) is added slowly to a solution of ethoxymethylene methylcyanoacetate (20.2 g.) in absolute ethanol ml.). A mild exothermic reaction occurs. The solution is heated six hours at reflux and then most of the solvent is distilled off. On cooling, a 96% yield of product melting at -136 C. is obtained.

EXAMPLE C Preparation of 3-amino-2-phenylpyrazole-4-carboxylic acid methyl ester Phenylhydrazine (14.04 g.) is added to a solution of ethoxymethylene methylcyanoacetate (20.2 g.) in absolute ethanol (100 ml.). After refluxing for six hours the reaction solution is cooled and the product is collected and recrystallized from absolute ethanol (100 ml.). The yield of recrystallized material is 97.5%, melting at 149.5150.5 C.

Analysis.-Theory (percent): C, 60.8; H, 5.1; N, 19.3. Found (percent): C, 60.96; H, 5.41; N, 19.29.

EXAMPLE D Preparation of ethoxyrnethylene isopropylcyanoacetate This preparation is run exactly as Example A, substituting isopropylcyanoacetate for methylcyanoacetate. The product boils at 104 C./0.4 mm., 12 1.4710.

EXAMPLE E Preparation of 3-amino-2-phenylsulfonylpyraZole-4- carboxylic acid isopropyl ester Benzenesulfonylhydrazine (13.6 g.) and ethoxymethylene isopropylcyanoacetate (14.6 g.) are dissolved in absolute ethanol (80 ml.). The solution is heated at reflux for six hours, part of the solvent is distilled oil and the product is filtered off after cooling. A yield of 13.5 g. of the product, melting at 1013 C. is obtained.

EXAMPLE F Preparation of 3-amino-4-cyano-2-phenylsulfonylpyrazole Benzenesulfonylhydrazide (9.35 g.) is dissolved in absolute ethanol by warming. Ethoxymethylene malononitrile (6.63 g.) is added to the solution at such a rate that a gentle boil is maintained. The reaction solution is heated for one hour after addition is completed. The product which separates on cooling is collected and dried. A 61% yield of the product, melting at 1745 C., is obtained. Recrystallization from ethanol raises the melting point to 182-3 C.

Analysis.-Theory: (percent): C, 48.37; H, 3.25; N, 22.57. Found (percent): C, 48.38; H, 3.37; N, 22.47.

EXAMPLE 1 Ten ml. of 1:5 acid (1 part propioniczS parts acetic) is added to a solution of nitrosylsulfuric acid prepare from sodium nitrite (0.72 g.) and sulfuric acid (5 ml.). The solution is cooled to 3 C. and 3-aminopyrazole-4- carboxylic acid methyl ester (1.41 g.) is added below 5 C. followed by a second portion of 1:5 acid (10 ml.) at the same temperature. The diazotization is completed by stirring for two hours at 3-5 C. This diazo solution is added to a cooled solution of 1-methyl-2-phenylindole (2.07 g.) in 1:5 acid (15 ml.). The mineral acid is neutralized by the addition of solid ammonium acetate maintaining the temperature at 10 C. or below. When the coupling is complete, water (500 ml.) is added with good stirring. The precipitated yellow product, 3-(4-methoxycarbonyl-3-pyrazolylazo)-1-methyl-2-phenylindole, is collected and washed well with water. The azo product produces bright yellow shades on polyester fibers.

EXAMPLE 2 3-amino-2-phenylsulfonylpyrazole 4 carboxylic acid isopropyl ester (3.09 g.) is diazotized as described in Example 1. The diazo solution is added to a cooled solution The compounds of the invention can be used for dyeing hydrophobic textile materials in the manner described in US. 2,880,050, 2,757,064, 2,782,187 and 3,043,827. The following example illustrates one method by which the azo compounds of the invention can be applied to polyof 2-pheny1indole (1.93 g.) in 1:5 acid (20 ml.). The 5 st t n t 1 coupling mixture .is neutralized by addition of solid am- 6 er 6X16 ma ena monium acetate keeping the temperature at 10 C. or EXAMPLE 33 z i When coupgng g g a g The azo compound of Example 4 (0.1 g.) is dissolved i fi i g i f l 10 in 10 cc. of Z-methoxyethanol. A small amount (3-5 cc.) azo)- gi y O 5 1 2 f y Iownmg g of a 3% sodium lignin sulfonate aqueous solution is l mgnan z elazo g added, with stirring, and then the volume of the bath obtame lmparts ast ye Ow S a es to p0 yester is brought to 300 cc. with water. 3 cc. of an anionic solvent carrier (Tanavol) is added to the bath and 10 grams of EXAMPLE 3 15 gb textile lfabriic mgdeb okf1 poy(ethlylgneoterephthalate) 3-amino 4 cyano-2-ethylpyrazole (1.37 g.) is diazo- 18 P ace t f at WOT mlnlltes ti d and coupled with hgcyanoethyl 2 h li d l out heat. The dyeing 1s carned out at the boil for one hour. (2.45 g.) in 1:5 acid solution as described in Example 1. The dyed fabflc 1S removed from the dyebafll and scoured The resulting azo compound, 3 (4-cyano-2-ethyl-3-pyp for 20 minutes at 80 C. in a solution containing 1 g./ l. azolylazo) 1 (2-cyanoethyl)-2-phenylindole produces 20 neutral soap and g./l. sodium carbonate. The fabric is yellow shades of excellent fastness to light on polyester then Tlnsed, dfled In an Oven at and heat sat fib removal of residual carrier) for 5 minutes at 350 C. EXAMPLE 4 The compounds of the invention can also be applied to polyester textile materials by the heat fixation technique 1:5 acid (10 ml.) is added, below 20 C., to a solution edscribed in U.S. Pat. 2,663,612 and in the American of nitrosylsulfuric acid prepared from NaNO (0.72 g.) a Dyestuff Reporter, 42, 1 (1953). Polyamide fibers can be and H SO (5 ml.). 5 amino-4-carbomethoxy-l-phenyldyed with the azo compounds by the dyeing method depyrazole (2.18 g.) is added keeping the temperature below scribed above except that no carrier is necessary. The 5 C. After addition of a second portion of 1:5 acid (10 a ove dyeing procedure also can be used for applying the ml.) at the same temperature, the diazotization is comazo compounds of the invention to cellulose acetate fibers pleted by stirring for 2 hours at 3-5 C. This diazo soluexcept ghat Ere carrier is omitted and the dyeing is carried tion is added to a cooled solution of l-methyl-Z-phenyl- Out t 0 indole (2.07 g.) in 1:5 acid (15 ml.). The mineral acid is Polymeric linear polyester materials of the terephthaneutralized by portionwise addition of solid N H OAc late sold under the trademarks Kodel, Dacron and keeplng the temperature below 10 C. when coupling was Terylene are illustrative of the linear aromatic polyester complete, as 1nd1cated by an R-salt test, water (500 ml.) textile materials that can be dyed with the compounds of is added and th pr d t collected on filter, Washed well our invention. Examples of linear polyester textile matewith water and dried at room temperature. The product, rials that can be dyed with the compounds of the inven- 3-(4-methoxycarbony1 2 phenyl 3 pyrazolylazo)-1- tion are those prepared from ethylene glycol and dimethmethyl-2-phenylindole, imparts fast yellow shades to fibers ylterephthalate or from cyclohexanedimethanol and diof cellulose esters, polyesters and polyamides. methylterephthalate. The novel azo compounds have been The azo compounds of the examples of the following found to give excellent dyeings on carpets containing table are obtained by the procedures described in Expoly(1,4 cyclohexylenedimethylene terephthalate) fiber. amples 1 and 4, using the appropriate aminopyrazoles and Polyesters prepared from cyclohexanedimethanol and diindoles. The compounds disclosed 1n the table give yellow methylterephthalate are more particularly described in dyeings on polyester fibers and conform to Formula I. U.S. Pat. 2,901,446. Poly(ethylene terephthalate) poly- Rz a R4 R5 R6 CN H CGH5 --OH; H -CN H OGH -CH2CH2CN H ON SO2CaH5 o5H CHzCH2CN H 88885 ae 011 a... -0000H H on1 H 3 1i 2 COOCH3 H CHa -OH3 H COOCH H CaH5 -CH2CH ON H s am 5011201120 8% -oooonicrnn SO2CGH5 4101i, -on n CO0CH(OH3)2 S02C6I{5 OH -GH3 H CN 5H5 -CtH5 C a H OONH2 -06H5 --OH CH CHgCN H NO2 CeH5 -COHs CH3 H ON CoH CH5 (CH2)3-NCOCH2CH2CO H 8% so o H CH 8% 8% H -CN -CO CgH: a O:H: ((HZ) NHo0CH a-oooom, oo0o2n5 s02o2H5 -otHi- -oon, (OH2)aNHSOzCH H -N0z COCuH4-p-Cl -CH3 -(CH2)aNCO-O-C5H4CO H NOz -COCH3 C5H5 -(OHz) NI-IOOCaH5 H as as assesses-see a -C0OCH -o.,1- r, 5 -C:H: OH2Cl12CONH 6 a H c00oH3 CH2CH(OH3)Z 06H CH2C6H5 6-0011; OOOCH; 05 5 CsH --CH CI-I C0OH H 43000113 otn5 -otH5 -(oH2 no 0o H2(:rm0 H CN -s02OtH O H CH; I-I -CN C6115 -C6H5 -'CH3 II CN CaH --Cn1-I -(CH2)aNHCOCH3 H ester fibers are described, for example, in US. Patent 2,465,319. The polymeric linear polyester materials disclosed in U.S. Pats. 2,945,010, 2,957,745 and 2,989,363, for example, can be dyed. The linear aromatic polyester materials specifically named have a melting point of at least 200 C. The poly(ethylene terephthalate) fibers which are dyed with the compounds of the invention are manufactured from a melt of a polymer having an inherent viscosity of at least 0.35 and preferably, about 0.6. The inherent viscosity of the poly(1,4-cyclhexylenedimethylene terephthalate) polymer is also at least 0.35. These inherent viscosities are measured at C. using 0.25 g. polymer per 100 ml. of a solvent consisting of 60% phenol and tetrachloroethane.

Examples of the polyamide fibers that can be dyed with the compounds of the invention are those consisting of nylon 66, nylon 6 and nylon 8. The cellulose acetate fibers that can be dyed include fibers having a basis of either cellulose triacetate of partially hydrolyzed cellulose acetate.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

We claim:

1. A compound having the formula N=N w 1 l (a. n

wherein and wherein each aryl group is phenyl or phenyl substituted with lower alkyl, lower alkoxy, chlorine, bromine, or nitro.

2. A compound according to claim 1 having the formula wherein R is cyano or lower alkoxycarbonyl;

R is lower alkyl, phenyl or phenylsulfonyl; and

R is lower alkyl, cyanoethyl, lower alkanoylamidopropyl, phenyl-NHCONHpropyl, or succinimidopropyl.

3. A compound according to claim 1 having the formula C OOCH;

4. A compound according to claim 1 having the formula 6. A compound according to claim 1 having the formula 7. A compound according to claim 1 having the formula I C H 0 H 0 H NHC 0 CH3 References Cited UNITED STATES PATENTS 3,435,022 3/1969 Voltz 260l47 CHARLES B. PARKER, Primary Examiner D. M. PAPUGA, Assistant Examiner US. Cl. X.R. 

